There are no USB ports in the Chevrolet Bolt that stay powered for charging a device when the vehicle is shut off.
To charge a device when not driving the Bolt EV:
- You could leave the Bolt ‘on’ but there is problems with that
- You can wire something up to the constant 12V panels in the fuse box, just be careful not to pull too much power out of it with the car off so you don’t drain the 12V auxiliary battery
- Buy a power bank, and leave it plugged into the car’s USB port. It will charge when the car is running, and when the car is shut off, it provides a way to charge a phone or other USB powered device without potential for draining the auxiliary battery. They can be purchased at almost every store, or bought online. Prices start around $15 on Amazon depending on battery capacity